Cholesterol is an essential component in the body and used in cell membranes. Excessive levels, however, can lead to hypercholesterolemia and atherosclerosis, which can result in coronary heart disease. Cholesterol is transported via: high-, low-, intermediate-, and very low-density lipoproteins; chylomicron remants; and chylomicrons. High levels of high-density lipoproteins are desirable because they transport cholesterol from the peripheral tissues to the liver, thereby maintaining cholesterol homeostasis. The main transport mechanism, however, is low-density lipoprotein, which moves cholesterol in the blood plasma and incorporates it into cell membranes. Increased levels of low-density lipoprotein, however, can interfere with uptake binding mechanisms.
Statin drugs such as atorvastatin, fluvastatin, pravastatin and simvastatin are often administered to those suffering from cholesterol issues. These drugs inhibit competitively 3-hydroxy-3-methylglutaryl coenzyme A reductase, thereby reducing cholesterol synthesis. Side effects of statins can include myositis, headache, rash, angioedema, gastrointestinal effects and altered liver functions. In addition, these drugs should not be used in patients with renal failure or in people with compromised liver function (Taylor et al. 2003).
Dietary fatty acid intake can influence many health factors, but much interest has been placed on the n-3 (omega-3) fatty acids. These essential fatty acids include α-linolenic (ALA), eicosapentaenoic (EPA) and docosahexaenoic acid (DHA). Various studies have shown that n-3 fatty acids are essential for normal growth and development. They may also play a critical role in the prevention and treatment of coronary heart disease, hypertension, diabetes and other inflammatory and autoimmune disorders (Simopoulos 1999). ALA is present in certain vegetable oils (flaxseed, cranberry seed, canola and chia) whereas EPA and DHA are found in fish, fish oil and algae products.
Between ethnic dietary groups it has been shown that the higher ratio of n-6 to n-3 in thrombocyte phospholipids can be a cause for a higher death rate from cardiovascular disease. This increased ratio also results in increased rates of type 2 diabetes, of which atherosclerosis is a major complication (Weber, 1991). Achieving target levels of n-3 fatty acids can be difficult with modern western diets deficient in ALA, EPA and DHA, and excessive in the n-6 linoleic acid. Target tissue concentrations for ALA and EPA can be met with consumption of ALA (Mantzioris et al. 2000). A primary cardiovascular benefit from n-3 fatty acid ingestion can be reduced blood clotting in vessel walls and reduced ventricular arrhythmias, (Zhao et al. (2004)). Some studies have found a dose-response relation between n-3 intake and beneficial effects on cardiovascular disease risk factors. Some studies have shown an inverse relationship between ALA intake and risk of sudden cardiac death (Albert et al. (2005)).
Policosanols can be defined as a mixture of long chain (C24-C36) aliphatic primary alcohols, which are commonly derived from sugar cane, rice bran, beeswax, wheat or sorghum. Predominant alcohols in this group are tetracosanol, hexacosanol, octacosanol and triacontanol.
Policosanols can lower cholesterol levels by inhibiting cholesterol biosynthesis via downregulation of 3-hydroxy-3-methylglutaryl Coenzyme A enzyme expression (Menendez et al. 1994, McCarty 2002). A study by Hernandez et al. (1992) found a reduction in serum cholesterol levels of subjects taking 20 mg policosanol per day for 4 weeks. Significant decreases in LDL levels, with increased levels of HDL were also noticed. Another double-blind randomized study by Castano, et al. (1999) investigated the effects of policosanol and pravastatin on the lipid profile in older hypercholesterelemic patients. Policosanol was found to increase HDL levels, but was also more effective than pravastatin in lowering LDL levels and the LDL:HDL ratio.
Policosanols can also protect lipoproteins from peroxidation, in both lipid and protein moieties (Menendez et al. 1999). This can be an important effect, since LDL oxidation is thought to be a necessary step in the development of atherosclerosis.
Policocanols may provide fewer side effects than statins, increase HDL cholesterol levels and have a reduced cost (Taylor et al. 2003).
One issue with policosanols are poor solubility, and difficulty with absorbtion in the gut. Human studies with [3H]-octacosanol showed the majority (81-91%) of total radioactivity was excredted in the feces, and only 1.2% of total radioactivity was found in urine (Mas, 2000).
Reducing parent the particle size of poorly solube compounds such as policosanol to a micron or sub-micron range, improved absorbtion and bioavailabilty is desirable.
Copending parent application Ser. No. 11/671,757 filed Feb. 7, 2006, discloses a human or animal dietary supplement composition that comprises a blood lipid health-effective amount of one or more long chain (C24-C36) primary alcohols (policosanols) dispersed in one or more food-grade fats or oils, wherein the particle sizes of the alcohols are substantially less than 10 microns.